High-energy terahertz pulses from organic crystals: DAST and DSTMS pumped at Ti:sapphire wavelength

High-energy terahertz pulses are produced by optical rectification (OR) in organic crystals 4-dimethylamino-N-methyl-4-stilbazolium tosylate (DAST) and 4-N,N-dimethylamino-4'-N'-methyl-stilbazolium 2,4,6-trimethylbenzenesulfonate (DSTMS) by a Ti: sapphire amplifier system with 0.8 mu m central wavelength. The simple scheme provides broadband spectra between 1 and 5 THz, when pumped by a collimated 60 fs near-IR pump pulse, and it is scalable in energy. Fluence-dependent conversion efficiency and damage threshold are reported, as well as optimized OR at visible wavelengths. (C) 2013 Optical Society of America